Method and device for operating a uv-radiation source

ABSTRACT

The invention relates to a method for operating a UV radiation source of the low-pressure gas discharge type. Said method comprises the following steps:—impingement of at least one heating coil with a heating voltage until the temperature of said coil has been increased;—impingement of the heating coil with a starting voltage in order to induce a gas discharge;—maintenance of the gas discharge by the application of a maintaining voltage and the disconnection of the heating voltage after the gas discharge has been started; in addition the following steps are preferably executed at any point in the method;—interrogation of an identification means that is connected to the UV radiation source and—if the response to the interrogation is negative, prevention or interruption of the operation,—if the response to the interrogation is positive, authorization of the operation. The invention also relates to a UV radiation source comprising a base body ( 20 ) and at least one connection zone which bears a number of electric connections ( 24, 25; 26, 27 ), whereby an identification means ( 28 ) that can be interrogated electrically is connected to the base body ( 20 ); and to a UV disinfection facility for fluids, in particular for water or waste water, said facility comprising at least one UV radiation source and an electric control and supply circuit that is located at a distance from the radiation source, whereby the control and supply circuit comprises an interrogation means which is suitable for verifying the presence of an identification means which is optionally assigned to the UV radiation source(s).

The specification incorporates by reference the disclosure of Germanpriority document 100 15 527.8 filed 30 Mar. 2000 and Internationalpriority document PCT/EP01/02562 filed 7 Mar. 2001.

The present invention is, of course, no way restricted to the specificdisclosure of the specification and drawings, byt also encompasses anymodifications within the scope of the appended claims.

BACKGROUND OF THE INVENTION

The present invention relates to a method for operating a UV radiationsource, a UV radiation source itself as well as a UV disinfectionfacility for fluids with a radiation source.

These kinds of method and devices have been known in practice for a longtime. In many cases so-called low-pressure mercury lamps are used as theUV radiation source, which with a high degree of efficiency emit UVlight of a wavelength which is suitable for destroying microorganisms influids. In this way effluent is disinfected without using chemicalswithin the presently valid limits, whereby the degree of disinfection isa function of the UV dose applied.

In particular with regard to compliance with applicable legal limits forlamp operation, in practice there is a problem that, firstly, theworking efficiency of the deployed lamps degrades the longer such lampsare in operation and, as a consequence thereof, such lamps must bereplaced after the expiration of a given operating time. Secondly, theoperational characteristics of a UV disinfection facility can bedisadvantageously altered if the lamps which are no longer usable arereplaced by third party manufacturer—sourced radiation lamps which arenot suitable with respect to their power or work efficiency rating toproduce the requisite high radiation power over the predicted operatinglife.

SUMMARY OF THE INVENTION

It is, therefore, the object of the present invention to provide amethod, a UV radiation source, as well as a UV disinfection facility inconnection with which the commencement of operation of the disinfectionfacility with a lamp which is not sourced from an authorizedmanufacturer cannot be undertaken without effort beyond the normal lampinstallation effort. In a further embodiment of the invention, eachindividual radiation source is to be individually identifiable and, tothe extent possible, is to be identified with the actually incurredoperating hours.

Due to the fact that selected locations are supplemented with anidentification means connected to the UV radiation source, and uponinterrogation, if the response to the interrogation is negative, theoperation is prevented or interrupted, and if the response to theinterrogation is positive, authorization for the operation is given, afacility can only be started up if the identification means is presentand is operating to identify the radiation source as an approvedradiation source.

Due to the fact that an identification means which can be interrogatedelectronically is connected to the base body, a control correspondinglyoriented for performing an interrogation of the identification means caninterrogate this identification means. Only a UV radiation source havingbeen provided with this identification means from an approvedmanufacturer and for this reason deemed authorized can then berecognized as authorized by a correspondingly oriented control.

Due to the fact that the control and supply circuit has an interrogationmeans, which is suitable for verifying the presence of one of the atleast one identification means, which has been selectively configured asa UV radiation source, the UV disinfection facility can requestinformation concerning the type and, therefore, the properties of the UVradiation source as well as, as desired, the condition of the UVradiation source and thereby make possible the commencement of operationof the interrogated UV radiation source with the origin of the UVradiation source being the decision criterion for the commencement ornot of the operation. In this manner, the commencement of operation ofnon-authorized radiation sources can be prevented.

In accordance with further details of the method of the presentinvention, it can be additionally provided that the interrogation stepis performed before the impingement of the radiation source with astarting voltage and, preferably, also before the impingement thereof aswell with a heating voltage. It can be provided that the identificationmeans contains information about the manufacturer and/or the type of theradiation source and, in this way not only the origin, but, as well, thepower, the emission characteristic, etc. can be established. If inaddition to this, the identification means also comprises informationindividually identifying the radiation source by way of a serial number,the use and operation of each such individually identified radiationsource can be monitored throughout its operational life.

The identification means can have a read-write memory which containsinformation concerning the cumulative operating life of the radiationsource. In this manner, the actual number of operating hours of aradiation source can be recorded and, indeed, can be recorded even ifthe respective radiation source has been removed from a disinfectionfacility before reaching its maximum operating life and thereafterre-inserted. Lack of certainty or ambiguity regarding the age of theradiation source cannot, therefore, arise.

If the radiation source, in accordance with the present invention, isfurther provided with identification means connected to the base body insuch a manner that a release of the identification means from the basebody would effect destruction of the identification means, deliberateunauthorized manipulation of the light source is also not possible. Theidentification means can, moreover, be an electronic circuit which isconnected by the electrical connections and, in this way, can beelectrically evaluated. In this connection, the identification means canhave two electrical connections and be electrically connected inparallel to a heating coil. The identification means can also have three(or more) electrical connections, two of which are electricallyconnected in parallel to a heating coil and at least a third connectionprovided for data transmission.

The identification means can alternatively be configured as atransponder, which conventionally receives and transmits in a wirelessmanner and which identifies the radiation source depending upon thereturn answer of the radiation source to an interrogation thereof.

Due to the fact that the UV disinfection facility is further outfittedsuch that the interrogation means is associated with an electronicstarting device, a data transmission can be effected directly via theconnecting wires of the UV radiation source. In this manner, theinterrogation means provided in the UV disinfection facility can beconnected via a 2-wire lead to the identification means assigned to theUV radiation source. The interrogation means can preferably exchangedata in the form of signals with the identification means, which aremodulated in correspondence with a heating voltage of a heating coil. Inthis manner, the number of electrical connecting wires required forconnection between the control and the UV radiation source is minimized.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention are described below withreference to the drawings, wherein:

FIG. 1: A flow chart of a method according to the invention, in which anidentification process is undertaken before the radiation source isactivated;

FIG. 2: A basic view of a radiation source in the form a low-pressuremercury lamp with a chip identifying it as the radiation source; as wellas

FIG. 3: A block diagram of an electronic starting device for use in a UVdisinfection facility and for performing the method of the presentinvention.

DESCRIPTION OF PREFERRED EMBODIMENTS

In FIG. 1, an operational diagram shown as a flow chart illustrates themethod of the present invention. This flow chart describes a variationof the method which is intended for UV lamps in which the identificationmeans is provided in the form of an electronic component extendingparallel to one of the two heating coils, the control of, and receipt ofinformation from, the identification means being accomplished via thetwo connecting wires which are anyway provided for the electrical supplyto the heating coil.

In the first step of the method, which precedes the actual operation,the identification circuit of the factory new, not previously insertedlamp is provided in the work location with a unique code. The codecontains both the identity of the manufacturer and the type of the lamp,as well as a unique serial number associated solely with the respectivelamp. This code is stored in a non-volatile memory, preferably EEPROM.

In operation, that is, when the lamp is deployed in a UV disinfectionfacility for effluent, initially, the method step 2 is performed inwhich the heating coils of the UV lamp are pre-heated via impingement bya heating voltage. The heating voltage in this case serves as a supplyvoltage for the identification circuit, which is connected in parallelto the heating coil. If the application of the pre-heat voltage isaccounted for, then, in the third step of the method, a signal operableas an interrogation sequence is modulated to correspond with thepre-heat voltage. The signal contains the interrogation information inthe form of a pulse sequence. In step 4 of the method, the presence andcorrelation of the code with the predefined values is confirmed by meansof a digital logic, which is integrated into the electronic start deviceof the respective lamp. If the code is not accepted, the lamp is notapproved for the given UV disinfection facility or, if the code is,moreover, entirely missing, step 5 of the method is selected by thedigital logic and the operational access to the facility is blocked atleast with respect to this one respective lamp.

If the code received in step 4 is recognized as valid, then step 6 ofthe method is performed whereupon the code is stored in the electronicstart device. In this manner, the lamp connected at the respectivelocation can be identified at a later operational time via reading ofthe identification stored in the electronic start device without theneed to repeat the interrogation process.

Then, in continuing with the performance of the method, step 7 isperformed in that the starting voltage is applied to the lamp, and,after the commencement of operation of the lamp, the operation ismaintained with the normal lighting voltage. After start up, thepre-heating, which was activated in step 2 of the method, isde-activated.

In regular operation, following the passage of a prescribed time in thestep 8 of the method, the pre-heating is again activated when the UVradiation source is in operation, in order to feed the identificationcircuit with its supply voltage. In step 9, the time expired since theperformance of step 7 is recorded in an operating hour counting—typedevice in the identification circuit. Thereafter, in step 10, thepre-heat voltage is again de-activated. Steps 8, 9 and 10 can, asdesired, be repetitively executed in a prescribed cycle such as, forexample, every 12 hours, so that, in the memory of the identificationcircuit, substantially real time current information about the operatinghours of the individual lamp accumulated up to the point is stored.

If the UV disinfection facility is shut down according to schedule, thepre-heat voltage is again activated in step 11 of the method and thefinal number of operating hours is transmitted to the identificationcircuit and stored therein. Then, the entire facility is de-activatedand remains so until the facility is re-activated in a step 12 of themethod. The new activation cycle begins again with step 2 of the methodas described herein above.

In the event that an unscheduled facility shut down occurs, during, forexample, a power failure occurring after step 10, the identificationcircuit will contain substantially real time current information aboutthe operating hours. The age of this information is, at the most, as oldas the most recent repeat cycle of steps 8-10.

The method described heretofore proceeds in a similar manner for theother identification circuits and identification means. In this manner,for example, a separate wire can be provided from the electronic startdevice to the identification means for data transmission purposes. If itis possible to omit the recording of the operating hours in theidentification means, then identification can alternatively be effectedin a wireless manner via a transponder, which only conveys a codewithout itself storing data. Also, in connection with this solution, itis ensured that, in step 4 of the method, an unapproved code will berecognized, and that the facility transitions to step 5 of the method toblock the operation, if unapproved lamps are used.

In this manner, it is ensured that the UV disinfection facility cannotbe operated if unapproved lamps are used, whereby the UV dose to whichthe effluent is exposed is below the stipulated level and, therefore,pathogenic microorganisms could possibly be released to the effluent.The method, therefore, operates to guarantee reliable operation,compliance with the prescribed limits, and, finally, protection of theenvironment against microbiological contamination.

In FIG. 2, a UV radiation source with an identification means configuredin accordance with the present invention is diagrammatically shown. Abase body 20 in the form of a gas-tight closed quartz tube forms aradiation volume 21, which contains a charge of gas as is conventionallyknown in connection with a low-pressure mercury lamp. A heating coil 22,22′ is arranged, respectively, on each end of the base body 20 in eachconfiguration, the connecting wires 24, 25; 26, 27 thereof leading outfrom the base body. These wires normally terminate in a ceramic base(not shown) and are configured as contact pins.

An identification means 28 in the form of an integrated circuit isprovided between the connecting wires 24, 25 of the heating coil 22. Theintegrated circuit, in this configuration, is secured to the ceramicbase due to thermal and mechanical considerations and the ceramic basesupports the connecting wires 24 and 25. The UV radiation source,excepting the identification circuit 28, is conventionally known. In thevariation shown with the contact to identification circuit 28 effectedvia the connecting wires 24, 25, the UV radiation source provided withthe identification means 28 remains compatible with facilities which arealready in operation without the inventive circuit.

Finally, in FIG. 3, an electronic start device is shown in a blockdiagram, the electronic start device being suitable for operating the UVradiation source illustrated in FIG. 2 and for implementing the methodas illustrated in the flow chart of FIG. 1.

The electronic start device includes a control 30, which controls a mainsupply circuit 31 as well as two voltage sources 32 to effectpre-heating of the heating coils 22, 22′. The control 30 also controls adigital logic 33 as well as a switch 34. *p+12X The outputs of thevoltage supply 32, as illustrated in FIG. 2, are connected to theconnecting wires 24, 25; 26, 27 of the radiation source.

The operation of the device is in accordance with the method describedwith respect to FIG. 1 in that, initially, control of the voltage source32 is undertaken to effect the pre-heating and, thereafter, closing ofthe switch 34 is undertaken, so that the digital logic 33 can modulatethe interrogation sequence executed via the leads 24, 25. The result ofthe read operation is evaluated by the digital logic 33 acting as anevaluation means and conveyed to the main supply circuit 31. If the lampconnected to the leads 24-27 is authorized to start operation, then theswitch 34 is opened and the start impulse is applied via the connectingwires 35, 36 to the connecting wires 25, 26. If the radiation source isactivated, then, consequently, only the maintenance voltage continues tobe fed to the radiation source from the main supply circuit. The voltagesupply 32 is then de-activated and is turned on again only if a new reador write operation is to be executed, as was described in detail inconnection with FIG. 1.

The commencement of operation of a lamp can also be blocked by a centralcontrol in a modification of the heretofore described operation, if oneof the lamps is not recognized as an authorized lamp.

1. A method for operating a UV radiation source of the low-pressure gasdischarge type, the UV radiation source having a heating coil which, inresponse to the impingement of selected voltages thereagainst, effectsthe discharging of gas, the method comprising: interrogating anidentification means, the identification means being associated with theUV radiation source such that a response by the identification means toan interrogation thereof is interpretable as an identifyingcharacteristic of the UV radiation source; in the event that a responseto the interrogation of the identification means positively correlateswith information indicating that operation of the respective associatedUV radiation source is authorized, permitting the operation of the UVradiation source to proceed as an authorized operation; and in the eventthat a response to the interrogation of the identification means doesnot positively correlate with information indicating that operation ofthe respective associated UV radiation source is authorized, interveningin connection with the operation of the respective associated UVradiation source such that at least one of a signal indicating thenon-authorized status of the respective associated UV radiation sourceand a disablement of the operation of the respective associated UVradiation source are affected.
 2. A method according to claim 1, whereinthe operation of the UV radiation source includes impinging the heatingcoil with a starting voltage to induce a gas discharge and interrogatingthe identification means is performed before impinging the heating coilwith a starting voltage.
 3. A method according to claim 1, whereininterrogating the identification means includes interrogating anidentification means containing information about at least one of themanufacturer and the type of radiation source.
 4. A method according toclaim 1, wherein interrogating the identification means includesinterrogating an identification means containing information uniquelyindividually associated with the radiation source in the form of aserial number.
 5. A method according to claim 1, wherein interrogatingthe identification means includes interrogating an identification meanshaving a read/write memory which contains information about theaccumulated operating life of the radiation source.
 6. A UV radiationsource, comprising: a base body; at least one connection area whichsupports a plurality of electrical connections; and an identificationmeans which can be electrically interrogated connected to the base body.7. A UV radiation source according to claim 6, wherein theidentification means is connected to the base body in a manner such thatthe identification means is destroyed if it is removed from the basebody.
 8. A UV radiation source according to claim 6, wherein theidentification means is an electronic circuit which is connected by theelectrical connections.
 9. A UV radiation source according to claim 6,wherein the identification means has two electrical connections and iselectrically connected in parallel to a heating coil.
 10. A UV radiationsource according to claim 6, wherein the identification means has threeelectrical connections and is electrically connected in parallel to aheating coil and a third connection is provided for data transmission.11. A UV radiation source according to claim 6, wherein theidentification means is a transponder.
 12. A UV disinfection facilityfor fluid disinfecting handling of, in particular, water or effluent,comprising: at least one UV radiation source; at least oneidentification means associated with the at least one UV radiationsource; and an electrical control and supply circuit spaced from thelight source, the electrical control and supply circuit including aninterrogation means which is configured for verifying the presence ofthe at least one identification means associated with the at least oneUV radiation source.
 13. A UV disinfecting facility according to claim12, and further comprising an electronic start device associated withthe identification means.
 14. A UV disinfecting facility according toclaim 12, wherein the interrogation means is connected with theidentification means via a two-wire lead.
 15. A UV disinfecting facilityaccording to claim 12, wherein the interrogation means and theidentification means exchange unidirectional or bi-directional data inthe form of signals, which are modulated to correlate with the voltageof a heating coil.
 16. A method according to claim 1, wherein theoperation of the UV radiation source includes impinging at least oneheating coil with a heating voltage to effect the heating thereof up toan increased heating coil temperature, impinging the heating coil with astarting voltage to induce a gas discharge, and maintaining thedischarging of gas by applying a maintenance voltage and de-activatingthe heating voltage after the step of impinging the heating coil with astarting voltage and interrogating an identification means is performedduring a selected time before, during, or after impinging the heatingcoil with a heating voltage, impinging the heating coil with a startingvoltage, or maintaining the discharging of the gas by applying amaintenance voltage to the heating coil.